Catálogo de publicaciones - revistas

<jats:p> Interferons must balance antiviral actions against immunosuppressive effects during acute and chronic infections. <jats:named-content content-type="related-content"> [Also see Reports by <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="202" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1235208"> Wilson <jats:italic>et al.</jats:italic> </jats:related-article> and <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="207" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1235214"> Teijaro <jats:italic>et al.</jats:italic> </jats:related-article> ] </jats:named-content> </jats:p>

<jats:title>Of Flies and Men</jats:title> <jats:p> Similarities of brain structure, function, and behavior are usually ascribed to convergent evolution. In their review, <jats:bold>Strausfeld and Hirth</jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="157" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1231828">157</jats:related-article> ) identify multiple commonalities shared by vertebrate basal ganglia and a system of forebrain centers in arthropods called the central complex. The authors conclude that circuits essential to behavioral choice originated very early across phyla. </jats:p>

<jats:title>Quantized and Anomalous</jats:title> <jats:p> The Hall effect, an electromagnetic phenomenon with a straightforward explanation, has many exotic counterparts, including a quantized version occurring independently of the presence of external magnetic fields. Inspired by a theoretical prediction of the quantum anomalous Hall (QAH) effect in magnetically doped topological insulator thin films, <jats:bold> Chang <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="167" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1234414">167</jats:related-article> , published online 14 March; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="153" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1237215">Oh</jats:related-article> </jats:bold> ) prepared thin films of the compound Cr0.15(Bi0.1Sb0.9)1.85Te3, with Cr as the magnetic dopant. They observed a plateau in the Hall resistance as a function of the gating voltage without any applied magnetic fields, signifying the achievement of the QAH state. </jats:p>

<jats:title>Fast and Young</jats:title> <jats:p> Type Ia supernovae are thought to result from the thermonuclear explosion of a white dwarf star accreting material from a companion star in a binary system. Their adoption as cosmic yardsticks has led to the discovery of the accelerated expansion of the universe. <jats:bold> Wang <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="170" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1231502">170</jats:related-article> , published online 7 March) show that supernovae with higher expansion velocities are located in the central, brighter regions of their host galaxies and are found in larger, more luminous galaxies, suggesting that they are associated with younger stellar populations. </jats:p>

<jats:title>More Criegee Sightings</jats:title> <jats:p> The reaction of ozone with unsaturated hydrocarbons produces short-lived molecules termed Criegee intermediates. The simplest such molecule, H <jats:sub>2</jats:sub> CO <jats:sub>2</jats:sub> , was recently detected and monitored in the laboratory. <jats:bold> Su <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="174" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1234369">174</jats:related-article> ; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="154" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1236475">Vereecken</jats:related-article> </jats:bold> ) have obtained its vibrational spectrum, which could ultimately enable direct measurements of its reactivity in the atmosphere. <jats:bold> Taatjes <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="177" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1234689">177</jats:related-article> ; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="154" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1236475">Vereecken</jats:related-article> </jats:bold> ) report on the laboratory preparation and reactivity of the next heavier Criegee intermediate, which bears a methyl group in place of one of the hydrogen atoms. </jats:p>

<jats:title>More Criegee Sightings</jats:title> <jats:p> The reaction of ozone with unsaturated hydrocarbons produces short-lived molecules termed Criegee intermediates. The simplest such molecule, H <jats:sub>2</jats:sub> CO <jats:sub>2</jats:sub> , was recently detected and monitored in the laboratory. <jats:bold> Su <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="174" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1234369">174</jats:related-article> ; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="154" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1236475">Vereecken</jats:related-article> </jats:bold> ) have obtained its vibrational spectrum, which could ultimately enable direct measurements of its reactivity in the atmosphere. <jats:bold> Taatjes <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="177" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1234689">177</jats:related-article> ; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="154" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1236475">Vereecken</jats:related-article> </jats:bold> ) report on the laboratory preparation and reactivity of the next heavier Criegee intermediate, which bears a methyl group in place of one of the hydrogen atoms. </jats:p>

<jats:title>Preparing Pactamycin</jats:title> <jats:p> Microbially derived organic compounds often have remarkably intricate structures that confer striking bioactivity, but such complexity may become an impediment to drug development. Pactamycin is one such case—a potent antibiotic used to probe ribosome structure and function that in its native form is too cytotoxic for therapeutic application. <jats:bold> Malinowski <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="180" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1234756">180</jats:related-article> ; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="152" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1236882">Codelli and Reisman</jats:related-article> </jats:bold> ) present a 15-step laboratory-scale synthesis of this molecule that offers prospects for the generation of structural analogs that could facilitate further exploratory medicinal research. </jats:p>

<jats:title>Permafrost Thaw Predictions</jats:title> <jats:p> Permafrost contains twice as much carbon as the atmosphere which could have serious consequences if it were to be released by widespread thawing. <jats:bold> Vaks <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="183" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1228729">183</jats:related-article> , published online 21 February) present a 450,000 year-long record of speleothem growth at selected locations in Siberia, which traces changes in the extent of permafrost over that time period. The authors conclude that conditions only slightly warmer than those of today would cause widespread thawing of continuous permafrost as far north as 60°N. </jats:p>

<jats:title>Van Allen Variation</jats:title> <jats:p> The two rings of relativistic particles called Van Allen Belts that encircle Earth were discovered during the space age, and are known to pose risks to satellites in geostationary orbit. NASA launched twin spacecraft, the Van Allen Probes, on 30 August 2012 to measure and characterize Earth's radiation belt regions. <jats:bold> Baker <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6129" page="186" related-article-type="in-this-issue" vol="340" xlink:href="10.1126/science.1233518">186</jats:related-article> , published online 28 February) have shown that a third, unexpected and temporary, radiation belt formed on 2 September 2012 to disappear 4 weeks later in response to changes in the solar wind. </jats:p>